John Mayer. (Ethan Miller/GETTY IMAGES)

In a post on his Tumblr, Mayer explained that a granuloma on one of his vocal cords that was removed last year has returned. He explained that his upcoming album, “Born and Raised,” will still be released May 22, but the growth has forced him to cancel his 21-stop tour indefinitely.

“Though there will be a day when all of this will be behind me, it will sideline me for a longer period of time than I care to have you count down,” Mayer said.

Indeed, this is another disappointing setback for fans of the singer/songwriter. Tour stops in Michigan, Rhode Island, Tennessee and other locations were already sold out.

“I’m pretty emotionally burnt out at the moment, but please know how hard I tried to resolve this and how disappointed I am that I can’t perform this record yet,” the 34-year-old explained. “The only thing that stops me from devolving into a puddle of tears is knowing that it’s a long life, and the greatest gift in the world is being able to create music no matter what the circumstances. So these are the new circumstances, and I’ll find a way to make it mean something. That’s all you can ever do.”